Communication networks are increasingly required to carry information at various data rates. The selected data rate for a given communication can be pre-established between the transmitter and receiver, can be signaled, for example, using handshaking techniques, or can be dynamically determined by the receiver. A static rate mechanism does not offer the flexibility required by most applications, and a signaling technique increases the acquisition latency.
A number of techniques have thus been proposed or suggested for automatic data rate detection. Such data rate detection techniques allow a receiver to determine the rate of incoming data, for example, by examining the received data. Such automatic data rate detection techniques allow a receiver to receive data from a variety of transmitting devices operating at different speeds without having to establish data rates in advance.
A need exists for improved methods and apparatus for determining the data rate of a received signal in a communication receiver. A further need exists for communications networks that support multiple data rates and dynamic data rate switching. Yet another need exists for communications networks that provide data rate detection in the physical layer using non-invasive data monitoring.